Testing a Mamiya 6MF before purchase?

I am looking at a Mamiya 6MF to puchase to give a whirl and take on an upcoming trip to Costa Rica. I have the opportunity to run a roll of film through it to check the focus of the 3 lenses. Anything else particular about these cameras? I have been researching online of quite a while and it seems that making sure all three lenses are calibrated to th RF correctly would be one of the bigger items to check. I plan on checking them all at infinity and also something 10-12 feet away. Thanks for you help!

Fire the shutter with the back open. You can put ground glass or paper over the film plane and check RF alignment.

Also check the collapsing mechanism and make sure it pops out properly; there will be a few knobs to verify.

Perhaps most important, check the winder and make sure it feels smooth and robust.

Keith,

I have checked the lens mount extention and collapse--worked smoothly. I will be sure to feel the winder mechanism as I cycle through some frames. If the RF is off, how much trouble is it to get it re-aligned?

I think there are still some folks who can do it. There are instructions online somewhere; I don't think realignment is a big hassle but it'd be better to get it CLAd at the same time by someone who knows what they're doing. Anyway you may not need realignment... I bought two bodies used and both are fine. Since you won't go faster than f/3.5 and you also can't focus closer than a meter or two... RF alignment may not be much of an issue